Paper/patches/server/0634-Prevent-excessive-velocity-through-repeated-crits.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Thu, 25 Nov 2021 10:25:09 +0100
Subject: [PATCH] Prevent excessive velocity through repeated crits


diff --git a/src/main/java/net/minecraft/world/entity/LivingEntity.java b/src/main/java/net/minecraft/world/entity/LivingEntity.java
index e54e41f2a94b19f9df3d087f88a2ceb6fc52d1dc..65ab2a1e47d9f338dbb13062d25f6c9a3d5cc7ff 100644
--- a/src/main/java/net/minecraft/world/entity/LivingEntity.java
+++ b/src/main/java/net/minecraft/world/entity/LivingEntity.java
@@ -2744,17 +2744,29 @@ public abstract class LivingEntity extends Entity implements Attackable {
         return this.hasEffect(MobEffects.JUMP) ? 0.1F * ((float) this.getEffect(MobEffects.JUMP).getAmplifier() + 1.0F) : 0.0F;
     }
 
+    protected long lastJumpTime = 0L; // Paper - Prevent excessive velocity through repeated crits
     @VisibleForTesting
     public void jumpFromGround() {
         float f = this.getJumpPower();
 
         if (f > 1.0E-5F) {
             Vec3 vec3d = this.getDeltaMovement();
+            // Paper start - Prevent excessive velocity through repeated crits
+            long time = System.nanoTime();
+            boolean canCrit = true;
+            if (this instanceof net.minecraft.world.entity.player.Player) {
+                canCrit = false;
+                if (time - this.lastJumpTime > (long)(0.250e9)) {
+                    this.lastJumpTime = time;
+                    canCrit = true;
+                }
+            }
+            // Paper end - Prevent excessive velocity through repeated crits
 
             this.setDeltaMovement(vec3d.x, (double) f, vec3d.z);
             if (this.isSprinting()) {
                 float f1 = this.getYRot() * 0.017453292F;
-
+                if (canCrit) // Paper - Prevent excessive velocity through repeated crits
                 this.addDeltaMovement(new Vec3((double) (-Mth.sin(f1)) * 0.2D, 0.0D, (double) Mth.cos(f1) * 0.2D));
             }